The present invention relates, in general, to a railcar hand brake, and more particularly, to an apparatus for a quick release mechanism in a railcar vertical wheel hand brake. The present invention will maintain a hand brake in the released position until an application is made.
Prior to the present invention, a railcar vertical hand brake includes a brake release mechanism that provides quick release of the brakes by disengaging the winding gear to permit free rotation of the main gear wheel. A force is exerted on the release lever to move the attached brake release shaft, whereby releasing the main gear wheel and the tension on the brake chain, which in turn releases the brake. When the force on the release lever is removed, the main gear wheel re-engages. However, the brake may not be fully released. When a railcar negotiates a curve in the track, the truck rotates and can exert a force on the brake chain. The chain resists the truck movement and tends to pull on the hand brake lever. This action can apply the brakes to the truck while the train is in motion. Friction and wear between the brake shoes and the wheels, and the wheels and the rail may occur as a result.
An example of this type hand brake is taught in U.S. Pat. No. 3,668,944, and the Universal 7400 Model Hand Brake. The teachings of these references are incorporated herein by reference thereto.
In a first aspect, the present invention provides an apparatus for a quick release mechanism in a railcar hand brake having a housing. The housing has a front casing with an inside wall of a predetermined size and shape, a back plate, and an operating shaft rotatably mounted in the housing, including a first end, a second end, and a ratchet wheel rotatable with the operating shaft intermediate of the first and second ends. A release shaft is rotatably mounted in the housing. The quick release mechanism comprises a projection of a predetermined size and shape disposed substantially perpendicular to the ratchet wheel, and a flexible clamp of a predetermined size and shape mounted inside the housing. A member is disposed substantially perpendicular to and about the circumference of the release shaft. A first element is disposed on such member wherein the first element interposes with the flexible clamp when the quick release shaft is rotated to achieve and maintain full brake release, and a second element is disposed on such member and engageable with the projection disposed on the ratchet wheel when the operating shaft is rotated to disengage the first element from the flexible clamp to allow for brake application.
In a further aspect, the present invention provides for a combination with a railcar hand brake having a brake chain, brake drum, gear mechanism, ratchet device further including a ratchet wheel, clutch device, quick release mechanism, and a housing adapted for mounting on a railcar. The improvement comprises a projection of a predetermined size and shape disposed substantially perpendicular to the ratchet wheel, and a flexible clamp of a predetermined size and shape mounted inside the housing. A member is disposed perpendicular to and about the circumference of the release shaft, with a first element disposed on said member wherein the first element interposes with the flexible clamp when the release shaft is rotated to achieve and maintain full brake release, and a second element disposed on said member and engageable with the projection when the operating shaft is rotated to disengage the first element from the flexible clamp to allow for brake application.
In a further aspect, the present invention provides an apparatus for a quick release mechanism in a railcar hand brake having a housing. The quick release mechanism comprises a release shaft of a predetermined size and shape rotatably mounted in the housing. The release shaft has a first end, and the first end includes a cavity of a predetermined size and shape. A release lever has a hub with an inside diameter which is journaled on the first end of the release shaft. A stop of a predetermined size and shape is disposed on the inside diameter of the hub of the release lever, and is engageable with the cavity of the release shaft to rotate the release shaft and cause free quick release of the brake.
In still a further aspect, the present invention provides for a combination with a railcar hand brake having a brake chain, brake drum, gear mechanism, ratchet device further including a ratchet wheel, clutch device, quick release mechanism, and a housing adapted for mounting on a railcar. The improvement comprises a release shaft of a predetermined size and shape rotatably mounted in the housing. The release shaft has a first end, the first end including a cavity of a predetermined size and shape. A release lever has a hub with an inside diameter which is journaled on the first end of the release shaft. A stop of a predetermined size and shape is disposed on the inside diameter of the hub of the release lever, and is engageable with the cavity of the release shaft to rotate the release shaft and cause free quick release of the brake.
It is therefore a primary object of the present invention to provide an apparatus for maintaining a railcar hand brake quick release mechanism in the full release position until brake application is made.
Another object of the present invention is to increase railcar wheel life by reducing the premature wear between the railcar brakes and the wheels as a result of friction between the brakes and the wheels due to unintentional brake application during train operation.
Still a further object of the present invention is to increase railway track life by reducing the friction between the wheels and the track as a result of restriction of rolling movement of the wheels on the track due to unintentional brake application during train operation.
Still a further object of the present invention is to minimize the potential for the quick release handle to remain extended into the path of the railcar ladder by allowing the release lever to freely return to the original position while maintaining full brake release.
In addition to the various objects of the invention that have been described above, various other objects and advantages of the invention will become more readily apparent to those persons skilled in the relevant art from the following more detailed description of the invention, particularly, when such description is taken in conjunction with the attached drawing figures and the appended claims.